Richard Rorty

Richard Rorty, who has died aged 75, was a rarity - an American philosopher who enjoyed a high reputation in France and Germany, and a public intellectual who was influential in literary theory and political thinking as well as in philosophy.

His philosophical heroes were an unlikely couple: "bad brother [Jacques] Derrida", as he called the postmodernist enfant terrible (obituary, October 11 2004), and the American analytic philosopher Donald Davidson (obituary, September 4 2003). But actually he was neither Continental nor analytic. In the American tradition of William James, Charles Peirce and John Dewey, he was a pragmatist, believing that "truth", rather than being the correspondence between words and reality, is what it is most advantageous in practice for us to believe. Knowing, he said, is "coping not copying". In pursuing truth we are not searching for correspondence to reality but for "the widest possible intersubjective agreement".

Rorty got his BA (1949) and MA (1952) at the University of Chicago, his PhD (1956) at Yale, taught at Wellesley College, Massachusetts (1958-61), and was Stuart professor of philosophy at Princeton (1961-82). At first just a jobbing analytic philosopher, he began to question his philosophical foundations in the early 1970s. The publication of Philosophy and the Mirror of Nature (1979) earned him accolades and abuse for its demolition of the basic assumptions of Anglo-American philosophy, and his reputation was further elevated with Consequences of Pragmatism 10 years later.

Characteristically disparaging the narrowness of philosophy departments, he became professor of humanities at the University of Virginia (1982-88), then professor of comparative literature at Stanford University, California, till 2005, after which he was professor emeritus. In 1981, he received one of the first MacArthur Foundation "genius grants".

Rorty was born in New York city. His maternal grandfather, Walter Rauschenbusch, a Baptist clergyman, had founded the 19th-century American social gospel movement, and his parents were writers whose New Jersey home was often a refuge for fellow Trotskyites. "I was just brought up a Trotskyist the way people are brought up Methodists or Jews or something like that. It was just the faith of the household." At the age of 12, Rorty felt certain that "the point of being human was to spend one's life fighting social injustice". But he became what he called a "liberal ironist", and succeeded in antagonising both the left and right in politics for what was considered his relativism, just as he enraged philosophers of all persuasions with his smug pragmatism.

The British philosopher Bernard Williams (obituary, June 13 2003), a great sympathiser with Nietzsche and other Continental thinkers, wrote of Rorty with palpable anger, accusing him of ignoring the vital part notions of truth, illusory or not, play in identifying and pursuing social goods, and of anyway relying on these very notions, plus those of Enlightenment optimism that he also claimed to reject.

Rorty certainly delighted in being provocative, even claiming that, despite George Orwell's famous "freedom is the freedom to say 2 + 2 = 4", the only real problem with Winston (in Nineteen Eighty-Four) coming to believe that 2 + 2 = 5 is that the belief is induced by torture, truth being irrelevant.

"Intellectuals", Rorty declared, "cannot live without pathos." He accused realists (those who believe in a reality that exists independent of human perceptions of it) of simply trying to gratify one of the urges previously satisfied by religion. "Theists find pathos in the distance between the human and the divine. Realists find it in the abyss separating human thought and language from reality, as it is in itself." Dubbing himself "raucously secularist", Rorty, in Philosophy and the Mirror of Nature, furthered Wilfred Sellars' attack on the "myth of the given", pooh-poohing the immemorial view of philosophy as an attempt to represent in thought and language a non-linguisitic reality. There is neither a physical, objective reality to be mirrored, he argued, nor non-physical minds to mirror it.

Attacking the traditional view that "to know is to represent accurately what is outside the mind", he urged us, instead, to "see knowledge as a matter of conversation and of social practice". Rorty, who professed himself mystified at the popularity outside academia of Philosophy and the Mirror of Nature, offered as a possible explanation that the book was perhaps seen as "a follow-up to [Thomas] Kuhn", the thinker who had been similarly non-foundationalist about the "truths", which he considered as shifting "paradigms", of science.

It also inveighed against Descartes' "invention of mind". Rorty imagined a planet of beings exactly like us except that they never use the sort of language of inner states that we do, but simply report on their brain states. They complain about "stimulated C-fibres" where we might complain about pain, and, commenting on mistaking a mastodon for an elephant, say something like "I had G-412 together with F-11, but then I had S-147, so I realised it must be a mastodon."

Having slashed away at the foundations of philosophy, Rorty was perfectly happy that there was no danger of philosophy "coming to an end", any more than there had been with religion when discredited. He wanted people to learn about philosophers of the past, but admitted he had no idea "what roles these men will play in our descendants' conversation". Having shrugged off objectivity and embraced something very like relativism, he was none the less a firm believer in the excellence of a liberal democratic society, because it encourages the existence of competing beliefs in a peaceful community.

He was always prolific, producing newspaper and magazine articles in addition to his academic output. Towards the end of his life, he became increasingly concerned with politics - keen to influence public political discussion, and to further democracy and liberalism.

He was fiercely critical of President George Bush and the Iraq War, and, in Achieving Our Country (1998), lamented the decay of the authentic social-democratic left. Reminded that many people thought it was impossible to die for a belief held pragmatically, he responded, "I hope they're wrong, but I can't prove it." Asked about his originality, he disclaimed having any. He had borrowed from Dewey and Derrida, Davidson and Wittgenstein, and married the thought of these dissonant philosophers. "It's just a talent for bricolage," he said.

All his life, he loved the outdoors, and for his last three decades was an avid birdwatcher. Orchids were another great passion. He is survived by his wife, biomedical ethicist Mary Varney, a son from his first marriage, and a daughter and son from his second marriage.

· Richard McKay Rorty, philosopher, born October 4 1931; died June 8 2007